If you heart the first post when filtering by "Best", but not the second, when you filter by "New" or "Rising", the first post still has the heart icon rendered despite it not being the post you gave a heart (and the second one which you gave a heart earlier when it was in the first position shows up as not "hearted").
If you heart the first post when filtering by "Best", but not the second, when you filter by "New" or "Rising", the first post still has the heart icon rendered despite it not being the post you gave a heart (and the second one which you gave a heart earlier when it was in the first position shows up as not "hearted").